Posts can not be saved with /etc/ as part of the content

[fgluck]

I created a post using the latest version of WordPress with one line and the only content of the post.

The line is:

/etc/

I can not save this post as a draft. When saving, I get a blank white screen.
This was tested using Theme TwentyFifteen updated to the latest version.

I can save the post if there is a space between /etc and the last slash.

This has been tested with all plugins disabled with the same results.

[SergeyBiryukov]

Hi @fgluck, welcome to WordPress Trac!

This sounds like a security rule set up by your hosting provider. There's no code in WordPress core that would prevent posts containing /etc/ from being saved.

Please try the support forums for troubleshooting: ​https://wordpress.org/support/.

Related: #25564, #25736.